Processing environments have various timing facilities, including time of day (TOD) clocks that are used to provide a high resolution measure of real time suitable for the indication of date and time of day. Processes within a processing environment rely on the time produced by these timing facilities to ensure reliable and accurate execution of the processes within the processing environment.
Various protocols have been developed to handle different aspects relating to the timing facilities. For example, time protocols have been developed to manage the synchronization of time between different clocks within and outside of the processing environment.
As a further example, protocols have been developed that enable control programs (e.g., non-application level programs) to obtain information concerning the quality of time produced by the timing facilities. For instance, in the current zSeries® servers, offered by International Business Machines Corporation, the LPAR hypervisor has direct access to time quality information. However, this information is not directly available to application programs. If an application program desires this information, it invokes supervisor services to obtain the information. This is costly, inefficient, and requires additional overhead.